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Ductless AC Evap Air Filters

Would like to get some non-bias feedback on what if any problems result from not running the air filters in the indoor unit. (Besides allowing larger dust particultes to accumulate in the coil.)

By non Bias, I meant not from the OEM or OEM Rep because as a former employee of an OEM I know they can sometimes give you a reason based on only theory or there could be way over-tight specs, etc. I'm looking for someone who actually saw shortened life, breakdown, etc from someone running without the air filters. I confess to being a mostly counter jockey but am involved in these kind of issues hence looking for the real feedback.

If you look at a filter and say "Damn, that dirty" Imagine it not being there. That dust will be pulled right into the motor. Causing the motor to overheat and DIE. While that is going on, the dust will collect on the fan blades and they wont have the cupping action anymore to throw the same amount of air as they are designed to do. Dirt will also collect on the heat exchanger of furnace making it not transfer heat as designed to, same for cooling coil. Dirt can also wear down the heat exchanger and cooling coils.....

That is just for beginners, there are more things that can occur, I am guilty of letting a machine run without them for minor amounts of time if it is a size I do not have with me, just to satisfy the house while I run and get the correct size. (Mainly only in heating season though)

I have run into this a few times. Besides the obvious dirty coil, I had one unit that the blower wheel was so caked up with muck that it burned out the motor. You can swap the motors in place, but you are almost better off pulling the unit off the wall. What a wicked pain.

If you look at a filter and say "Damn, that dirty" Imagine it not being there. That dust will be pulled right into the motor. Causing the motor to overheat and DIE. While that is going on, the dust will collect on the fan blades and they wont have the cupping action anymore to throw the same amount of air as they are designed to do. Dirt will also collect on the heat exchanger of furnace making it not transfer heat as designed to, same for cooling coil. Dirt can also wear down the heat exchanger and cooling coils.....

That is just for beginners, there are more things that can occur, I am guilty of letting a machine run without them for minor amounts of time if it is a size I do not have with me, just to satisfy the house while I run and get the correct size. (Mainly only in heating season though)

Thank you Sir, for the great feedback. I have seen units caked as you say, even with the filters in, (nicotine is a good adhesive for dust).

Filters save a lot of grunt work. On mini-split wall units, which I believe you are asking about, are a pain in the butt to get apart. If pulling a filter and washing it in the sink every now and then prevents that, then go for it. Now, I will say we have some homes that are SO clean that those filters never show any dirt. Now I suppose in a home like that, you can live without a filter. But no telling how much daily cleaning staff costs... but these are 1% type problems. Hahaha

Filters save a lot of grunt work. On mini-split wall units, which I believe you are asking about, are a pain in the butt to get apart. If pulling a filter and washing it in the sink every now and then prevents that, then go for it. Now, I will say we have some homes that are SO clean that those filters never show any dirt. Now I suppose in a home like that, you can live without a filter. But no telling how much daily cleaning staff costs... but these are 1% type problems. Hahaha

We do lots of Mitsubishi's which aren't too bad to get apart but are little tricky. I agree on the clean homes. We have many older, retired folks and 2nd home owners with areas that are pretty darn clean too. I always tell people, if you have cats, dogs, live on a dirt road and kids in and out, you should probably check them pretty frequently.